A variety of medical approaches have been devised for treatment of obesity, including diet, medication and surgery. In general, surgery is reserved for patients in whom conservative measures, such as monitoring caloric intake or controlling appetite with appetite suppressants, have failed. In addition, surgery is generally reserved for patients who are seriously overweight.
There have been many surgical approaches to obesity. For example, some patients have received implantation of one or more bulking prostheses to reduce stomach volume. The prosthesis limits the amount of food the stomach can hold and causes the patient to feel full. U.S. Published Patent Application No. 20030040804 to Stack et al., for example, describes a tubular prosthesis that induces feelings of satiety within a patient. Another approach is restrictive surgery, which surgically makes the stomach smaller by removing or closing a section of the stomach. This procedure also causes the patient to feel full. U.S. Published Patent Application No. 20020183768 to Deem et al., which describes a recent proposal for treating obesity, describes various techniques for reducing the size of the stomach pouch to limit caloric intake as well as to provide an earlier feeling of satiety.
Another surgical procedure to treat obesity is the gastric bypass procedure. In the gastric bypass procedure, the surgeon creates a small stomach pouch to restrict food intake and constructs a bypass of the duodenum and other segments of the small intestine. This procedure limits the amount of food that is completely digested or absorbed. Surgical interventions such as these are very invasive, and each form of surgery may involve complications. Restrictive surgery may entail a risk of vomiting, for example, and gastric bypass surgery may result in unpleasant consequences known as “dumping syndrome.”
Another technique for treatment of obesity involves administration of therapeutic agents, such as drugs. For example, extensive research and development has been conducted with respect to appetite suppressants, resulting in limited efficacy and, in many cases, undesirable side effects. Also, PCT Publication No. WO/0187335 to Uhlman et al. describes administration of agents to selectively inhibit ghrelin activity. Recent studies suggest that ghrelin is a potent appetite stimulant in animals and man when administered orally.
Another surgical technique is described in U.S. Pat. No. 6,427,089 to Knowlton. In particular, Knowlton describes a surgical technique for causing a contraction or reduction in the volume of the stomach by the delivery of thermal energy to the stomach wall. According to Knowlton, the technique relies on a microwave device to heat a submucosal layer of tissue within the stomach wall without thermal damage of the mucosa of the stomach. A resulting thermal lesion causes contraction of the preexisting collagen matrix of the stomach wall. A further technique is described in PCT Publication No. WO 00/69376 to Edwards in which nerves responsible for the sensations of hunger are ablated by applying energy to the interior mucosal lining of the stomach. The mucosal lining of the stomach, which is responsible for protecting the stomach tissue and producing stomach acid necessary for digestion, is ablated along with the specified nerves.
Table 1 below lists documents that disclose techniques for treatment of obesity.
TABLE 1Patent NumberInventorsTitle20020183768Deem et al.Obesity treatment tools and methods20030040804Stack et al.Satiation devices and methodsWO/0187335Uhlman et al.Method for selectively inhibiting ghrelinaction6,427,089KnowltonStomach treatment apparatusand method5,782,798RiseTechniques for treating eating disordersby brain stimulation and drug infusionWO 00/69376EdwardsSurgical weight control device5,423,872CigainaProcess and device for treating obesityand syndromes related to motor dis-orders of the stomach of a patient5,188,104Wernicke et al.Treatment of eating disorders by nervestimulation
All documents listed in Table 1 above are hereby incorporated by reference herein in their respective entireties. As those of ordinary skill in the art will appreciate readily upon reading the Summary of the Invention, Detailed Description of the Preferred Embodiments and claims set forth below, many of the devices and methods disclosed in the patents of Table 1 may be modified advantageously by using the techniques of the present invention.